linux-kernel - Re: [PATCH v2 3/3] X86: Add a thread cpu time implementation to vDSO

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20141219112350.GJ30905@twins.programming.kicks-ass.net>
Date:	Fri, 19 Dec 2014 12:23:50 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Andy Lutomirski <luto@...capital.net>
Cc:	Shaohua Li <shli@...com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	X86 ML <x86@...nel.org>, Kernel-team@...com,
	"H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>,
	John Stultz <john.stultz@...aro.org>
Subject: Re: [PATCH v2 3/3] X86: Add a thread cpu time implementation to vDSO

On Thu, Dec 18, 2014 at 04:22:59PM -0800, Andy Lutomirski wrote:
> Bad news: this patch is incorrect, I think.  Take a look at
> update_rq_clock -- it does fancy things involving irq time and
> paravirt steal time.  So this patch could result in extremely
> non-monotonic results.

Yeah, I'm not sure how (and if) we could make all that work :/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/